Endoscopic operation portion and endoscope

ABSTRACT

A holder which is disposed inside an endoscopic operation section and which fixes the flexible substrate, includes a first opening to pass the flexible substrate into the holder from the outside of the holder, a cavity portion which has a ceiling portion in the inner circumferential surface thereof and in which the flexible substrate is disposed in a bent state inside the holder, and a second opening to pass the flexible substrate to the outside of the holder from the inside of the holder. The flexible substrate is disposed separately from the ceiling portion of the cavity portion in a state where the flexible substrate protruding to the outside of the holder from the first opening and the second opening is fixed to the outer circumference of the holder.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of PCT Application No.PCT/JP2015/060225, filed Mar. 31, 2015 and based upon and claiming thebenefit of priority from prior Japanese Patent Application No.2014-088520, filed Apr. 22, 2014, the entire contents of all of whichare incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an endoscopic operation section and anendoscope.

2 Description of the Related Art

For example, as disclosed in International Publication No. 2013/154106,a flexible substrate having key portions is used in an operation sectionof an endoscope to suitably operate an illumination optical system andan observation optical system. In a state where the flexible substrateis held to a holder, the holder is attached to an operation section mainbody.

BRIEF SUMMARY OF THE INVENTION

According to one aspect of the present invention, an endoscopicoperation section to operate an endoscope, includes: an elasticallydeformable belt-shaped flexible substrate which is disposed inside theendoscopic operation section and which has a switch function; and aholder which is disposed inside the endoscopic operation section andwhich fixes the flexible substrate, the holder including: a firstopening to pass the flexible substrate into the holder from the outsideof the holder, a cavity portion which has a ceiling portion in the innercircumferential surface thereof and in which the flexible substrate isdisposed in a bent state inside the holder, and a second opening to passthe flexible substrate to the outside of the holder from the inside ofthe holder, wherein the flexible substrate is disposed separately fromthe ceiling portion of the cavity portion in a state where the flexiblesubstrate protruding to the outside of the holder from the first openingand the second opening is fixed to the outer circumference of theholder.

Advantages of the invention will be set forth in the description whichfollows, and in part will be obvious from the description, or may belearned by practice of the invention. Advantages of the invention may berealized and obtained by means of the instrumentalities and combinationsparticularly pointed out hereinafter.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate embodiments of the invention, andtogether with the general description given above and the detaileddescription of the embodiments given below, serve to explain theprinciples of the invention.

FIG. 1 is a schematic diagram showing an endoscope according to oneembodiment;

FIG. 2 is a schematic diagram showing the endoscope according to oneembodiment;

FIG. 3 is a schematic front view showing a state where a holder to holda flexible substrate is attached to an operation section main bodyequipped with a press unit in an operation section of the endoscopeaccording to one embodiment;

FIG. 4 is a schematic front view showing the operation section main bodyequipped with the press unit in the operation section of the endoscopeaccording to one embodiment;

FIG. 5A is a schematic diagram showing the flexible substrate providedinside the operation section of the endoscope according to oneembodiment;

FIG. 5B is a schematic sectional view taken along the line 5B-5B in FIG.5A;

FIG. 6A is a schematic plan view showing the holder provided inside theoperation section of the endoscope according to one embodiment;

FIG. 6B is a schematic perspective view showing the vicinity of the topof the holder provided inside the operation section of the endoscopeaccording to one embodiment;

FIG. 7A is a schematic plan view showing a state where the holderprovided inside the operation section of the endoscope according to oneembodiment is seen from the side opposite to that in FIG. 6A;

FIG. 7B is a schematic perspective view showing the vicinity of the topof the holder provided inside the operation section of the endoscopeaccording to one embodiment;

FIG. 8A is a schematic plan view showing a first attachment surface ofthe holder provided inside the operation section of the endoscopeaccording to one embodiment;

FIG. 8B is a schematic plan view showing a second attachment surface ofthe holder provided inside the operation section of the endoscopeaccording to one embodiment;

FIG. 9 is a schematic sectional view of the vicinity of the top of theholder provided inside the operation section of the endoscope accordingto one embodiment, taken along the line IX-IX in FIG. 7A;

FIG. 10 is a schematic perspective view showing a state where a firstbelt-shaped portion of the flexible substrate is placed to face a secondopening of the holder provided inside the operation section of theendoscope according to one embodiment;

FIG. 11 is a schematic top view showing a state where the firstbelt-shaped portion and a first key attachment portion of the flexiblesubstrate are protruded toward the first attachment surface through afirst opening from a second opening of the holder provided inside theoperation section of the endoscope according to one embodiment, and asecond belt-shaped portion is disposed between the second opening andthe first opening;

FIG. 12 is a schematic top view showing a state where the flexiblesubstrate is moved in a direction that intersects at right angles withthe longitudinal direction of the flexible substrate relative to theholder provided inside the operation section of the endoscope accordingto one embodiment, as compared to the state shown in FIG. 11;

FIG. 13A is a schematic perspective view showing a state where thesecond belt-shaped portion of the flexible substrate is disposed betweenthe first and second openings of the holder provided inside theoperation section of the endoscope according to one embodiment;

FIG. 13B is a schematic sectional view showing a state where the secondbelt-shaped portion of the flexible substrate is disposed between thefirst and second openings of the holder provided inside the operationsection of the endoscope according to one embodiment;

FIG. 14A is a schematic perspective view showing a state where while thesecond belt-shaped portion of the flexible substrate is disposed betweenthe first and second openings of the holder provided inside theoperation section of the endoscope according to one embodiment, thefirst belt-shaped portion is guided to a first passage, the first keyattachment portion is attached to the first attachment surface, a thirdbelt-shaped portion is guided to a second passage, and a second keyattachment portion is attached to the second attachment surface; and

FIG. 14B is a schematic sectional view showing a state where while thesecond belt-shaped portion of the flexible substrate is disposed betweenthe first and second openings of the holder provided inside theoperation section of the endoscope according to one embodiment, thefirst belt-shaped portion is guided to the first passage, the first keyattachment portion is attached to the first attachment surface, thethird belt-shaped portion is guided to the second passage, and thesecond key attachment portion is attached to the second attachmentsurface.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, one embodiment of this invention will be described withreference to the drawings.

As shown in FIG. 1, an endoscope 10 includes an operation section 12 tooperate the endoscope 10, and an insertion section 14 coupled to theoperation section 12. The operation section 12 is provided on theproximal side of the insertion section 14 along a longitudinal directionL1. The insertion section 14 has a distal hard portion 22, a curvingportion 24, and a flexible tubular portion 26 from the distal end to theproximal end in order along the longitudinal direction L1. The proximalend of the flexible tubular portion 26 is connected to the operationsection 12.

The operation section 12 has a universal cord 32. The universal cord 32has, at the distal end to a later-described operation section main body52, a connector 34 which is connected to a controller including a lightsource device and a camera control unit that are not shown.

As shown in FIG. 2, an illumination optical system 42 and an observationoptical system 44 are provided in parallel inside the operation section12 and the insertion section 14 of the endoscope 10. The illuminationoptical system 42 and the observation optical system 44 are controlledto perform suitable functions when first and second press portions 74and 76 of a later-described press unit 58 are pressed.

As shown in FIG. 3, the operation section 12 includes the operationsection main body (exterior case) 52 serving as an outer shell, anelastically deformable belt-shaped flexible substrate 54 which isdisposed inside the operation section main body 52 and which has aswitch function, and a holder (substrate frame) 56 which is disposedinside the operation section main body 52 and which fixes the flexiblesubstrate 54. The operation section 12 further includes the press unit58 which can independently press each of later-described first andsecond key portions 104 and 106. As shown in FIG. 1, the operationsection 12 includes a grasp portion 60 coupled to the operation sectionmain body 52. The grasp portion 60 is grasped by a user together withthe operation section main body 52. The grasp portion 60 is coupled tothe proximal end of the flexible tubular portion 26 of the insertionsection 14 via an anti-breakage portion 60 a.

The operation section main body 52 shown in FIG. 3 and FIG. 4 cooperateswith the grasp portion 60 to serve as the exterior case of the operationsection 12. The operation section main body 52 is made of aheat-resistant, chemical-resistant, and insulating hard material such asdenatured polyphenylether (PPE). The operation section main body 52 hasa holder attachment portion 82, supporting columns 84 a and 84 b, and alid portion 86 (see FIG. 1).

The holder attachment portion 82 is formed inside the operation sectionmain body 52. The holder attachment portion 82 defines an internal spaceof the operation section main body 52. The holder 56 is provided in theholder attachment portion 82 in a state where the flexible substrate 54is held to the upper end (proximal end) on the upper side (the proximalside along the longitudinal direction L1) of the operation section mainbody 52. That is, the holder 56 is provided inside the operation sectionmain body 52 in a state where the flexible substrate 54 is held.

The holder attachment portion 82 includes first and second inner facingsurfaces 82 a and 82 b. The first and second inner facing surfaces 82 aand 82 b face each other.

The press unit 58 is fitted and attached to the first and second innerfacing surfaces 82 a and 82 b. The first and second inner facingsurfaces 82 a and 82 b hold therebetween the holder 56 to which theflexible substrate 54 is held. The first and second inner facingsurfaces 82 a and 82 b may be formed as flat surfaces or curvedsurfaces. The angle between the first and second inner facing surfaces82 a and 82 b is preferably formed as, for example, an acute angle. Whenthe press unit 58 is attached to the operation section main body 52 andwhen the holder 56 to which the flexible substrate 54 is held isattached, the first inner facing surface 82 a faces a first outer facingsurface 142 of a body 132 of the holder 56, and the second inner facingsurface 82 b faces a second outer facing surface 144 of the body 132 ofthe holder 56.

The operation section main body 52 has the supporting columns 84 a and84 b which support the holder 56 at a position on the proximal side (theupper end in FIG. 3) of the insertion section 14 along the longitudinaldirection L1 to keep a state where the holder 56 is provided in(supported on) the holder attachment portion 82.

Although not shown, a rotation knob to curve the curving portion 24 isprovided outside the operation section main body 52, and a known bendingdrive mechanism which rotates together with the rotation of the rotationknob is provided inside the operation section main body 52. In a statewhere these mechanisms are provided, the operation section main body 52is covered with the lid portion 86.

Switching vales 62 and 64 of a water/air supply unit and a suction unitare provided in the operation section main body 52. The switching vales62 and 64 are provided in parallel in the later-described second pressportion 76.

It is preferable that the press unit 58 includes an integral plate 72,and the first and second press portions 74 and 76. The plate 72 and thefirst and second press portions 74 and 76 are made of a heat-resistantand insulating soft resin material such as a silicone resin material.That is, the plate 72 and the first and second press portions 74 and 76are materials that are flexible enough for the operation section mainbody 52.

Here, as shown in FIG. 4, the press unit 58 includes a holding member 78which holds the plate 72 and the first and second press portions 74 and76 to the operation section main body 52. The holding member 78 isformed into a substantially rectangular shape using a heat-resistant andinsulating hard resin material such as polypropylene. The holding member78 is made of a material that is harder than the press portions 74 and76 and softer than the operation section main body 52.

The first press portion 74 has a press body 74 a which is operated bythe thumb of the left hand of the user when the operation section 12 isgrasped with, for example, the left hand of the user of the endoscope10. The second press portion 76 has first to third press bodies 76 a, 76b, and 76 c which are suitably operated by the first finger and secondfinger of the user's left hand when the operation section 12 is graspedwith, for example, the left hand of the user of the second endoscope 10.

A later-described key body 104 a of the flexible substrate 54 faces thepress body 74 a of the first press portion 74. Later-described keybodies 106 a, 106 b, and 106 c of the flexible substrate 54 face thepress bodies 76 a, 76 b, and 76 c of the second press portion 76,respectively.

The press bodies 74 a, 76 a, 76 b, and 76 c are preferably configured tocooperate with the key bodies 104 a, 106 a, 106 b, and 106 c to providea click feel to the user when the press bodies 74 a, 76 a, 76 b, and 76c are pressed toward the key bodies 104 a, 106 a, 106 b, and 106 c.

The flexible substrate 54 shown in FIG. 5A and FIG. 5B are belt-shapedand elastically deformable. The flexible substrate 54 has a basematerial 102 in which unshown conducting wires are provided, the firstand second key portions 104 and 106 which are disposed on the frontsurface of the base material 102 and which are pressed from the outsideof the operation section main body 52 and thereby operated, a firstadhesive portion (not shown) formed on the surface (the rear surface ofthe base material 102) of the base material 102 opposite to the firstkey portion 104, a first mold release sheet 110 (see FIG. 13A) attachedto the first adhesive portion, a second adhesive portion 112 formed onthe surface (the rear surface of the base material 102) opposite to thesecond key portion 106, and a second mold release sheet 114 attached tothe second adhesive portion 112. Double-sided tape may be used as thefirst adhesive portion and the second adhesive portion 112.

The base material 102 of the flexible substrate 54 is preferably formedinto a flexible belt shape using, for example, a polyimide resinmaterial or a polyethylene resin material. The base material 102 isadhesively bonded to and wound around the holder 56.

The base material 102 of the flexible substrate 54 includes flexiblefirst to third belt-shaped portions 122 a, 122 b, and 122 c, a first keyattachment portion 124 a in which the first key portion 104 is provided,and a second key attachment portion 124 b in which the second keyportion 106 is provided. The first key attachment portion 124 a isprovided between the first and second belt-shaped portions 122 a and 122b. The second key attachment portion 124 b is provided between thesecond and third belt-shaped portions 122 b and 122 c. That is, theflexible second belt-shaped portion 122 b is provided between the firstand second key attachment portions 124 a and 124 b.

Here, the first belt-shaped portion 122 a, the first key attachmentportion 124 a, the second belt-shaped portion 122 b, the second keyattachment portion 124 b, and the third belt-shaped portion 122 c areprovided along a longitudinal direction L2 of the flexible substrate 54.Here, the first key attachment portion 124 a is displaced relative tothe second key attachment portion 124 b in a direction that intersectsat right angles with the longitudinal direction L2. More specifically,central axes L2′ of the first belt-shaped portion 122 a and the firstkey attachment portion 124 a are provided coaxially with each other inthe longitudinal direction L2. Central axes (the longitudinal directionL2) of the second belt-shaped portion 122 b, the second key attachmentportion 124 b, and the third belt-shaped portion 122 c are providedcoaxially with each other in the longitudinal direction L2. The centralaxis L2′ of the first key attachment portion 124 a is provided to bedisplaced parallel to the central axis (the longitudinal direction L2)of the second key attachment portion 124 b.

Each of the belt-shaped portions 122 a, 122 b, and 122 c has a widthsmaller than the width (a width in the direction that intersects atright angles with the longitudinal direction L2) of each of the keyattachment portions 124 a and 124 b. In contrast, each of thebelt-shaped portions 122 a, 122 b, and 122 c is sufficiently thinnerthan the width thereof. Therefore, each of the belt-shaped portions 122a, 122 b, and 122 c minimizes twisting and can yet be easily bent in twodirections opposite to each other. Specifically, the second belt-shapedportion 122 b can be bent and deformed so that the rear surfaces of thekey attachment portions 124 a and 124 b substantially face each other.

The length of each of the belt-shaped portions 122 a, 122 b, and 122 calong the longitudinal direction L2 is suitably adjusted. The length ofthe second belt-shaped portion 122 b along the longitudinal direction L2in particular is adjusted so that the second belt-shaped portion 122 bis loosely provided between a ceiling portion 138 a and a bottom surfaceportion 138 b, described later, without contacting the ceiling portion138 a and the bottom surface portion 138 b.

The first key portion 104 has the key body 104 a which faces the pressbody 74 a of the first press portion 74. The key body 104 a is formed onone surface (front surface) of the first key attachment portion 124 a.

The second key portion 106 has the first key body 106 a which faces thefirst press body 76 a of the second press portion 76, the second keybody 106 b which faces the second press body 76 b of the second pressportion 76, and the third key body 106 c which faces the third pressbody 76 b of the second press portion 76. The key bodies 106 a, 106 b,and 106 c are formed on one surface (front surface) of the second keyattachment portion 124 b. That is, all the key bodies 104 a, 106 a, 106b, and 106 c are provided on one surface (the same surface) of the basematerial 102.

The key bodies 104 a, 106 a, 106 b, and 106 c are electrically connectedto the connector 34 of the universal cord 32. For example, if the keybody 104 a is pressed, a control signal is transmitted to an unshowncontrol unit through the connector 34. Similarly, if each of the firstto third key bodies 106 a, 106 b, and 106 c is pressed, each ofdifferent control signals is transmitted to the unshown control unitthrough the connector 34. Thus, the illumination optical system 42and/or the observation optical system 44 can suitably be operated bypressing the key bodies 104 a, 106 a, 106 b, and 106 c.

First engagement recesses (engagement portions) 126 a and 126 b whichcan engage with first engagement protrusions (engagement protrusions)186 a and 186 b formed in a later-described first attachment surface 152of the holder 56 are formed in the first key attachment portion 124 a.The first engagement recesses (engagement recesses) 126 a and 126 b areformed as, for example, circular openings. The first key attachmentportion 124 a is attached in a state to be positioned in the firstattachment surface 152. Here, the two first engagement recesses 126 aand 126 b are separate from each other in the direction that intersectsat right angles with the longitudinal direction L2 of the flexiblesubstrate 54.

Second engagement recesses (engagement portions) 128 a and 128 b whichcan engage with second engagement protrusions (second engagementportions) 188 a and 188 b formed in a later-described second attachmentsurface 154 of the holder 56 are formed in the second key attachmentportion 124 b. The second engagement recesses 128 a and 128 b are formedas, for example, oblong openings. The second key attachment portion 124b is attached in a state to be positioned in the second attachmentsurface 154. Here, the two second engagement recesses 128 a and 128 bare separate from each other along the longitudinal direction L2 of theflexible substrate 54.

As shown in FIG. 5A, the second key attachment portion 124 b has a firstabutment position 129 a at a position to abut on a later-described firstbent portion 156 a of the second attachment surface 154, and has asecond abutment position 129 b at a position to abut on a second bentportion 156 b.

As shown in FIG. 5B, the second adhesive portion 112 has a coatedportion 112 a which is coated with an adhesive agent, and an uncoatedportion 112 b which is not coated with the adhesive agent. The coatedportion 112 a is formed around the second engagement recesses 128 a and128 b and the first and second abutment positions 129 a and 129 b. Incontrast, the uncoated portion 112 b having no adhesive agent in thesecond adhesive portion 112 is formed at positions corresponding to theinsides of the second engagement recesses 128 a and 128 b and positionscorresponding to the first and second abutment positions 129 a and 129b. That is, the first and second abutment positions 129 a and 129 b arenot coated with the adhesive agent. The second mold release sheet 114covers the whole second adhesive portion 112 including the coatedportion 112 a and the uncoated portion 112 b with one sheet-shapedmaterial. That is, the flexible substrate 54 has, in the surface of thesecond key attachment portion 124 b opposite to the surface to which thesecond key portion 106 is attached, the coated portion 112 a which iscoated with an attachment agent such as an adhesive agent to the secondattachment surface 154, the uncoated portion 112 b which is not coatedin parts corresponding to the abutment positions 129 a and 129 b, andthe mold release sheet 114 which integrally covers the coated portion112 a and the uncoated portion 112 b and can be released from the coatedportion 112 a.

Thus, as compared to the case where the second mold release sheet isseparated into parts, work can be easily done when the second keyattachment portion 124 b of the flexible substrate 54 according to thisembodiment is attached to the second attachment surface 154.

The holder 56 shown in FIG. 6A to FIG. 9 is made of a heat-resistant andinsulating hard resin material such as polypropylene. The holder 56 ismade of a material which is harder than the plate 72 and the holdingmember 78 of the press unit 58 and which has about the same hardness asthe operation section main body 52. That is, the operation section mainbody 52 and the holder 56 may have the same hardness, the operationsection main body 52 may be harder than the holder 56, or the operationsection main body 52 may be softer than the holder 56.

As shown in FIG. 6A to FIG. 7B, the holder 56 includes the body 132,first and second openings (opening edges) 134 and 136, and a cavityportion 138 to dispose the flexible substrate 54 in a bent state insidethe holder 56.

The body 132 has leg portions 132 a and 132 b which are supported on thesupporting columns 84 a and 84 b provided in the holder attachmentportion 82 of the operation section main body 52. As indicated by a sign132 c, the part between the leg portions 132 a and 132 b is continuouslyformed by a smooth flat surface of a curved surface.

The body 132 is preferably block-shaped to exert a press force to pressthe inner circumferential surface of the operation section main body(exterior case) 52 to the outside, but may be substantially V-shapeddepending on the selection of materials. In this embodiment, the body132 of the holder 56 is block-shaped, and has holes 132 d that reduceits weight while maintaining strength.

The body 132 has the first and second outer facing surfaces 142 and 144facing the press unit 58, and first and second side surfaces 146 and 148which are provided between the first and second outer facing surfaces142 and 144 (the later-described first and second attachment surfaces152 and 154) and which separate from each other. The angle between thefirst and second outer facing surfaces 142 and 144 is preferably anacute angle. The first and second side surfaces 146 and 148 arepreferably, for example, parallel to each other. Each of the first andsecond outer facing surfaces 142 and 144 and each of the first andsecond side surfaces 146 and 148 are adjacent to a top (couplingsurface) 150. That is, the top 150 is provided between the first andsecond outer facing surfaces 142 and 144. The top 150 is also providedbetween the first and second side surfaces 146 and 148. That is, the top150 is provided between the first and second outer facing surfaces 142and 144 (the first and second attachment surfaces 152 and 154) andbetween the first and second side surfaces 146 and 148.

The first attachment surface 152 to which the first key attachmentportion 124 a of the flexible substrate 54 is attached is formed in thefirst outer facing surface 142. The first attachment surface 152 isrecessed relative to the first outer facing surface 142. The width ofthe first attachment surface 152 that intersects at right angles with alongitudinal direction L3 is preferably formed to be slightly largerthan the width of the first key attachment portion 124 a of the flexiblesubstrate 54.

The second attachment surface 154 to which the second key attachmentportion 124 b of the flexible substrate 54 is attached is formed in thesecond outer facing surface 144. The second attachment surface 154 isrecessed relative to the second outer facing surface 144. The width ofthe second attachment surface 154 that intersects at right angles withthe longitudinal direction L3 is preferably formed to be slightly largerthan the width of the second key attachment portion 124 b of theflexible substrate 54.

In this embodiment, the first key attachment portion 124 a of theflexible substrate 54 is displaced in the direction that intersects atright angles with the longitudinal direction L2 thereof. Thus, the edgeof the first attachment surface 152 is closer to the first side surface146 than the edge of the second attachment surface 154. In other words,the distance between the first attachment surface 152 and the first sidesurface 146 is smaller than the distance between the second attachmentsurface 154 and the first side surface 146.

The second attachment surface 154 includes a first attachment region 154a which fixes the rear surface of the part of the second key attachmentportion 124 b in which the first key body 106 a is provided, a secondattachment region 154 b which fixes the rear surface of the part inwhich the second key body 106 b is provided, and a third attachmentregion 154 c which fixes the rear surface of the part in which the thirdkey body 106 c is provided. The attachment regions 154 a, 154 b, and 154c are provided along the longitudinal direction L3 in this order. Eachof the first to third attachment regions 154 a, 154 b, and 154 c ispreferably formed into a flat surface. Thus, the press unit 58 canindependently press the second key portion 106.

The second attachment surface 154 preferably has the bent portions 156 aand 156 b. The first bent portion 156 a is formed between the first andsecond attachment regions 154 a and 154 b. The second bent portion 156 bis formed between the second and third attachment regions 154 b and 154c. The first bent portion 156 a brings the normal to the secondattachment region 154 b closer to a state to intersect at right angleswith the longitudinal direction L1 than the first attachment region 154a. The second bent portion 156 b brings the normal to the thirdattachment region 154 c closer to a state to intersect at right angleswith the longitudinal direction L1 than the second attachment region 154b.

As shown in FIG. 8A and FIG. 8B, the first and second attachmentsurfaces 152 and 154 are formed substantially in the center of the widthdirection that intersects at right angles with the longitudinaldirection L3 in the first and second outer facing surfaces 142 and 144,respectively. Specifically, the edges of the first and second attachmentsurfaces 152 and 154 are formed to be displaced in the width directionin accordance with the displacement of the first and second keyattachment portions 124 a and 124 b relative to the longitudinaldirection L2 of the flexible substrate 54 shown in FIG. 5.

In the body 132, the first opening 134 is formed at the upper end of thefirst attachment surface 152, that is, at the end close to the top 150,and the second opening 136 is formed at the upper end of the secondattachment surface 154, that is, at the end close to the top 150.

A first passage 182 which brings the first belt-shaped portion 122 a ofthe flexible substrate 54 toward the lower side of the body 132 of theholder 56 is formed at the lower end (the end separate from the top 150)of the first attachment surface 152. A second passage 184 which bringsthe third belt-shaped portion 122 c of the flexible substrate 54 towardthe lower side of the body 132 of the holder 56 is formed at the lowerend (the end separate from the top 150) of the second attachment surface154.

The first engagement protrusions 186 a and 186 b are formed in the firstattachment surface 152. Each of the first engagement protrusions 186 aand 186 b is, for example, disk-shaped or column-shaped. The firstengagement protrusions 186 a and 186 b are separate in the widthdirection that intersects at right angles with the longitudinaldirection L3 of the first attachment surface 152. The first engagementrecesses 126 a and 126 b of the first key attachment portion 124 a ofthe flexible substrate 54 can be positioned on the first engagementprotrusions 186 a and 186 b of the first attachment surface 152.

The second engagement protrusions 188 a and 188 b are formed in thesecond attachment surface 154. Each of the second engagement protrusions188 a and 188 b is formed, for example, into a columnar shape having anelliptic edge. The second engagement protrusions 188 a and 188 b areseparate along the longitudinal direction L3 of the second attachmentsurface 154. The second engagement recesses 128 a and 128 b of thesecond key attachment portion 124 b of the flexible substrate 54 can bepositioned on the second engagement protrusions 188 a and 188 b of thesecond attachment surface 154.

As shown in FIG. 9, the cavity portion 138 communicates with the firstand second openings 134 and 136. The cavity portion 138 has, in itsinner circumferential surface (the inner circumferential surface of theholder 56), the ceiling portion 138 a formed closer to the upper side(proximal side) along the longitudinal direction L1 than the first andsecond openings 134 and 136, that is, at a position closer to the top150. The cavity portion 138 also has the bottom surface portion 138 bfacing the ceiling portion 138 a. The bottom surface portion 138 b isformed as the bottom surface of the second opening 136. That is, thecavity portion 138 has the bottom surface portion 138 b which is closerto the lower edge than the ceiling portion 138 a, that is, located onthe side separate from the top 150 and which faces the ceiling portion138 a and which houses the second belt-shaped portion 122 b in aseparate state.

Here, a first recess 134 a which is continuous with the first opening134 and which has the same shape as the first opening 134 is formed in adirection that intersects, for example, at right angles or substantiallyat right angles with the longitudinal direction L1 of the insertionsection 14 of the endoscope 10. An opening edge having the same shape asthe first opening 134 is not formed in the second attachment surface154. That is, the first opening 134 has the same shape in the directionthat intersects at right angles or substantially at right angles withthe longitudinal direction L1, and does not pierce from the firstattachment surface 152 to the second attachment surface 154. In thisway, it is preferable that the shape is the same from the first opening134 to a distal end 134 b of the first recess 134 a to the first opening134. For example, between the first attachment surface 152 and thesecond attachment surface 154, a space which is continuous with thefirst opening 134 is formed in a region located substantially ⅓ of thedistance from the first attachment surface 152 to the second attachmentsurface 154. Such a space is preferably formed by a die, but may beformed by a removal process.

A second recess 136 a which is continuous with the second opening 136and which has the same shape as the second opening 136 is formed in adirection that intersects, for example, at right angles or substantiallyat right angles with the longitudinal direction L1. An opening edgehaving the same shape as the second opening 136 is not formed in thefirst attachment surface 152. That is, the second opening 136 has thesame shape in the direction that intersects at right angles orsubstantially at right angles with the longitudinal direction L1, anddoes not pierce from the second attachment surface 154 to the firstattachment surface 152. In this way, it is preferable that the shape isthe same from the second opening 136 to a distal end 136 b of the secondrecess 136 a to the second opening 136. For example, between the secondattachment surface 154 and the first attachment surface 152, a spacewhich is continuous with the second opening 136 is formed in a regionlocated substantially ⅔ from the second attachment surface 154 to thefirst attachment surface 152. Such a space is preferably formed by adie, but may be formed by a removal process.

In the body 132, a third opening (opening edge) 172 (see FIG. 6A andFIG. 6B) which communicates with the cavity portion 138 at the upperedge of the first side surface 146 is formed, and a fourth opening(opening edge) 174 (see FIG. 7A and FIG. 7B) which communicates with thecavity portion 138 at the upper edge of the second side surface 148 isformed. That is, the third opening 172 which communicates with thecavity portion 138 is formed in the first side surface 146, and thefourth opening 174 which communicates with the cavity portion 138 andwhich is continuous with the ceiling portion 138 a is formed in thesecond side surface 148.

A third recess 172 a which is continuous with the third opening 172 andwhich has the same shape as the third opening 172 is formed in adirection that intersects, for example, at right angles or substantiallyat right angles with the longitudinal direction L1. An opening edgehaving the same shape as the third opening 172 is not formed in thesecond side surface 148. That is, the third opening 172 has the sameshape in the direction that intersects at right angles or substantiallyat right angles with the longitudinal direction L1, and does not piercefrom the first side surface 146 to the second side surface 148. In thisway, it is preferable that the shape is the same from the third opening172 to a distal end 172 b of the third recess 172 a to the third opening172. For example, between the first side surface 146 and the second sidesurface 148, a space which is continuous with the third opening 172 isformed in a region located substantially ⅔ of the distance from thefirst side surface 146 to the second side surface 148. Such a space ispreferably formed by a die, but may be formed by a removal process.

A fourth recess 174 a which is continuous with the fourth opening 174and which has the same shape as the fourth opening 174 is formed in adirection that intersects, for example, at right angles or substantiallyat right angles with the longitudinal direction L1. An opening edgehaving the same shape as the fourth opening 174 is not formed in thefirst side surface 146. That is, the fourth opening 174 has the sameshape in the direction that intersects at right angles or substantiallyat right angles with the longitudinal direction L1, and does not piercefrom the second side surface 148 to the first side surface 146. In thisway, it is preferable that the shape is the same from the fourth opening174 to a distal end 174 b of the fourth recess 174 a to the fourthopening 174. For example, between the first side surface 146 and thesecond side surface 148, a space which is continuous with the fourthopening 174 is formed in a region located substantially ⅔ the distancefrom the second side surface 148 to the first side surface 146. Such aspace is preferably formed by a die, but may be formed by a removalprocess.

As shown in FIG. 6B, FIG. 7B, FIG. 8A, and FIG. 9, the first opening 134and the first recess 134 a have a width (opening amount) greater thanthe width of the first attachment surface 152 of the flexible substrate54 that intersects at right angles with the longitudinal direction L3,and are substantially T-shaped to dispose the second belt-shaped portion122 b of the flexible substrate 54. As shown in FIG. 8B and FIG. 9, thesecond opening 136 and the second recess 136 a have a width (openingamount) greater than the width of the second attachment surface 154 ofthe flexible substrate 54 that intersects at right angles with thelongitudinal direction L3.

As shown in FIG. 6A, FIG. 6B, and FIG. 9, the third opening 172 and thethird recess 172 a are formed into a substantially triangular shape. Asshown in FIG. 7A, FIG. 7B, and FIG. 9, the fourth opening 174 and thefourth recess 174 a are substantially U-shaped or substantiallyV-shaped.

The first to fourth recesses 134 a, 136 a, 172 a, and 174 a cooperate toform the cavity portion 138.

The fourth opening 174 is continuous with the ceiling portion 138 a. Thesecond opening 136 is continuous with the bottom surface portion 138 b.The cavity portion 138 is formed by the third recess 172 a to secure thespace of a cavity for the second belt-shaped portion 122 b of theflexible substrate 54, and is formed by the fourth recess 174 a toincrease the distance of the ceiling portion 138 a from the bottomsurface portion 138 b.

As shown in FIG. 9, the distal end 172 b to the third opening 172 andthe distal end 174 b to the fourth opening 174 are formed by the thirdand fourth recesses 172 a and 174 a. The space between the distal ends172 b and 174 b, that is, the width of the ceiling portion 138 a has awidth greater than the width of the second belt-shaped portion 122 b ofthe flexible substrate 54 that intersects at right angles with thelongitudinal direction L2.

The cavity portion 138 according to this embodiment has a guide portion192 which guides the flexible substrate 54, and a housing portion(housing space) 194 which houses the second belt-shaped portion 122 b ofthe flexible substrate 54. The guide portion 192 and the housing portion194 are adjacent to each other.

The guide portion 192 guides the first belt-shaped portion 122 a and thefirst key attachment portion 124 a of the flexible substrate 54 into thecavity portion 138 from the outside of the body 132 through the secondopening 136, and guides the first belt-shaped portion 122 a and thefirst key attachment portion 124 a of the flexible substrate 54 to theoutside of the body 132 from the inside of the cavity portion 138through the first opening 134. The first opening 134 and the secondopening 136 allow the flexible substrate 54 to be passed into the holder56 from the outside of the holder 56, and allow the flexible substrate54 to be passed to the outside of the holder 56 from the inside of theholder 56.

The housing portion 194 has the bottom surface portion 138 b which iscloser to the lower end (the position separate from the top 150) alongthe longitudinal direction L1 than the ceiling portion 138 a and whichfaces the ceiling portion 138 a. The bottom surface portion 138 b iscontinuous with the third recess 172 a of the third opening 172. Theceiling portion 138 a is continuous with the fourth recess 174 a of thefourth opening 174. The housing portion 194 cooperates with the guideportion 192 to guide the flexible substrate 54 and form a space in whichthe second belt-shaped portion 122 b is bent between the bottom surfaceportion 138 b and the ceiling portion 138 a and in which the secondbelt-shaped portion 122 b can be housed separately from the ceilingportion 138 a when the first key attachment portion 124 a is attached tothe first attachment surface 152 from the second opening 136 to thefirst opening 134 through the flexible substrate 54 and when the secondkey attachment portion 124 b is attached to the second attachmentsurface 154. It is preferable that the second belt-shaped portion 122 bbeing housed in the housing portion 194 is not only separate from theceiling portion 138 a but also separate from the bottom surface portion138 b. That is, the second belt-shaped portion 122 b is not beingsupported on the holder 56 (is floating).

In this embodiment, it is preferable that the guide portion 192 islocated closer to the second side surface 148 than the first sidesurface 146 and the housing portion 194 is located closer to the firstside surface 146 than the second side surface 148 because the first andsecond key attachment portions 124 a and 124 b of the flexible substrate54 are displaced in the direction that intersects at right angles withthe longitudinal direction L2 of the flexible substrate 54.

Next, a manufacturing process to attach the flexible substrate 54 to theholder 56 according to this embodiment and attach the holder 56 to whichthe flexible substrate 54 is attached to the operation section main body52 in which the press unit 58 is provided is briefly described.

As shown in FIG. 10, the end of the first belt-shaped portion 122 a ofthe flexible substrate 54 is placed to face the second opening 136 ofthe second attachment surface 154 of the holder 56. Further, the end ofthe first belt-shaped portion 122 a of the flexible substrate 54 isplaced into the second opening 136 of the second attachment surface 154of the holder 56, and the first belt-shaped portion 122 a and the firstkey attachment portion 124 a are then pulled out of the first opening134 through the cavity portion 138.

In this instance, as shown in FIG. 11, the first key attachment portion124 a is displaced from the first attachment surface 152, and the secondkey attachment portion 124 b is displaced from the second attachmentsurface 154. Thus, as shown in FIG. 12, in a state where the secondbelt-shaped portion 122 b is provided in the cavity portion 138 betweenthe first and second openings 134 and 136, the flexible substrate 54 ismoved in the direction that intersects at right angles with thelongitudinal direction L2 thereof and in the direction that intersectsat right angles with the longitudinal direction L3 of the first andsecond attachment surfaces 152 and 154.

In this instance, as shown in FIG. 13A and FIG. 13B, the secondbelt-shaped portion 122 b is separate from the ceiling portion 138 a ofthe cavity portion 138. The second belt-shaped portion 122 b is separatefrom the bottom surface portion 138 b of the cavity portion 138. Tensileforce applied to the second belt-shaped portion 122 b is minimized, andthe second belt-shaped portion 122 b is loose. The second belt-shapedportion 122 b is disposed between the distal end 172 b to the thirdopening 172 and the distal end 174 b to the fourth opening 174.

In this state, the first mold release sheet 110 on the rear surface ofthe first key attachment portion 124 a of the flexible substrate 54 isdetached. Further, the first belt-shaped portion 122 a of the flexiblesubstrate 54 is placed into the first passage (lower end opening) 182 ofthe first attachment surface 152 and then guided to the rear surface ofthe first attachment surface 152, and the first engagement recesses 126a and 126 b of the first key attachment portion 124 a are engaged withthe first engagement protrusions 186 a and 186 b of the first attachmentsurface 152. Thus, the rear surface of the first key attachment portion124 a is attached to the first attachment surface 152 by the firstadhesive portion. Therefore, the key body 104 a in the front surface ofthe first key attachment portion 124 a is held to the first attachmentsurface 152.

Similarly, the second mold release sheet 114 (see FIG. 5B) on the rearsurface of the second key attachment portion 124 b of the flexiblesubstrate 54 is detached. Further, the third belt-shaped portion 122 cof the flexible substrate 54 is placed into the second passage (lowerend opening) 184 of the second attachment surface 154 and then guided tothe rear surface of the second attachment surface 154, and the secondengagement recesses 128 a and 128 b of the second key attachment portion124 b are engaged with the second engagement protrusions 188 a and 188 bof the second attachment surface 154. Thus, the rear surface of thesecond key attachment portion 124 b is attached to the second attachmentsurface 154 by the second adhesive portion 112. Therefore, the keybodies 106 a, 106 b, and 106 c in the front surface of the second keyattachment portion 124 b are held to the second attachment surface 154.More specifically, the first key body 106 a is held to the firstattachment region 154 a of the second attachment surface 154, the secondkey body 106 b is held to the second attachment region 154 b, and thethird key body 106 c is held to the third attachment region 154 c.

In the case according to the present embodiment, the three key bodies106 a, 106 b, and 106 c are provided in the front surface of the secondkey attachment portion 124 b, but one second mold release sheet 114 isprovided on the rear surface of the second key attachment portion 124 b.Thus, work can be more easily done to attach the second key attachmentportion 124 b to the second attachment surface 154 than when a moldrelease sheet is present on the rear side of each of the key bodies 106a, 106 b, and 106 c.

As shown in FIG. 14A and FIG. 14B, the flexible substrate 54 is held bythe holder 56 as above. At this point, as shown in FIG. 14B, the secondbelt-shaped portion 122 b is separate from each of the ceiling portion138 a and the bottom surface portion 138 b of the cavity portion 138.That is, in a state where the flexible substrate 54 protruding to theoutside of the holder 56 from the first opening 134 and the secondopening 136 is fixed to the outer circumference of the holder 56, thesecond belt-shaped portion 122 b of the flexible substrate 54 isdisposed separately from the ceiling portion 138 a of the cavity portion138 formed in the inner circumferential surface of the cavity portion138. This prevents force that detaches the first and second keyattachment portions 124 a and 124 b from the first and second attachmentsurfaces 152 and 154 from being continuously applied, for example, as ina state where the second belt-shaped portion is in abutment with theceiling portion. Moreover, the second belt-shaped portion 122 b isloose. This minimizes the application of tensile force to the secondbelt-shaped portion 122 b.

The holder 56 holding the flexible substrate 54 is then provided in theholder attachment portion 82 of the operation section main body 52. Inthis instance, it is preferable to press the holder 56 into theoperation section main body 52 in which the press unit 58 is provided tosuppress the shaking of the holder 56 relative to the operation sectionmain body 52 to the minimum. The leg portions 132 a and 132 b of thebody 132 of the holder 56 are then engaged with the supporting columns84 a and 84 b of the operation section main body 52. In this way, theholder 56 which holds the flexible substrate 54 is provided in theoperation section main body 52.

At this point, the key body 104 a faces the press body 74 a, the keybody 106 a faces the first press body 76 a, the key body 106 b faces thesecond press body 76 b, and the third key body 106 c faces the thirdpress body 76 c. The third belt-shaped portion 122 c is electricallyconnected to the connector 34 via a conducting wire provided in theuniversal cord 32.

A bending operation knob and a bending drive mechanism are then providedin a space at the lower end of the operation section main body 52.

In addition, after the grasp portion 60 and the universal cord 32 areattached to the operation section main body 52, the lid portion 86 isdisposed in the operation section main body 52 to form the operationsection 12. The insertion section 14 is suitably attached to theoperation section 12 to form the endoscope 10.

The following can be said according to the endoscope 10 in thisembodiment.

The cavity portion 138 of the holder 56 can guide the flexible substrate54 into the cavity portion 138 from the outside of the body 132 throughthe second opening 136 and guide the flexible substrate 54 to theoutside of the body 132 from the inside of the cavity portion 138through the first opening 134. When the first key attachment portion 124a is attached to the first attachment surface 152 and the second keyattachment portion 124 b is attached to the second attachment surface154, the second belt-shaped portion 122 b can be housed separately fromthe ceiling portion 138 a of the cavity portion 138. This can preventthe application of force to the second belt-shaped portion 122 b, andminimize the application of force that detaches the first and second keyattachment portions 124 a and 124 b from the first and second attachmentsurfaces 152 and 154 to the first and second key attachment portions 124a and 124 b adjacent to the second belt-shaped portion 122 b.

The second belt-shaped portion 122 b of the flexible substrate 54 isfloating with a proper degree of looseness to form spaces between thesecond belt-shaped portion 122 b and both the ceiling portion 138 a andthe bottom surface portion 138 b of the cavity portion 138. This notonly minimizes the pressing of the second belt-shaped portion 122 b bythe ceiling portion 138 a but can also prevent the force that detachesthe first and second key attachment portions 124 a and 124 b from thefirst and second attachment surfaces 152 and 154 from being applied dueto the application of tensile force to the first and second keyattachment portions 124 a and 124 b because the length of the secondbelt-shaped portion 122 b is too short.

Furthermore, it can be easily imagined that attachment work is difficultif the second belt-shaped portion 122 b is pressed with the ceilingportion 138 a when the first key attachment portion 124 a of theflexible substrate 54 is attached to the first attachment surface 152 ofthe holder 56 and when the second key attachment portion 124 b of theflexible substrate 54 is attached to the second attachment surface 154of the holder 56. In contrast, in this embodiment, the ceiling portion138 a and the second belt-shaped portion 122 b are separate from eachother even when the first key attachment portion 124 a of the flexiblesubstrate 54 is attached to the first attachment surface 152 of theholder 56 and when the second key attachment portion 124 b of theflexible substrate 54 is attached to the second attachment surface 154of the holder 56. Thus, workability of positioning and attachment can beimproved when the first key attachment portion 124 a of the flexiblesubstrate 54 is attached to the first attachment surface 152 of theholder 56 and when the second key attachment portion 124 b of theflexible substrate 54 is attached to the second attachment surface 154of the holder 56.

Therefore, according to this embodiment, it is possible to provide theendoscopic operation section 12 and the endoscope 10 which can keep thekey portions 104 and 106 of the flexible substrate 54 disposed atdesired positions of the holder 56.

Here, the three key bodies 106 a, 106 b, and 106 c can be positionedmerely by detaching one second mold release sheet 114 of the second keyattachment portion 124 b of the flexible substrate 54 having the keybodies 106 a, 106 b, and 106 c and then attaching the key bodies 106 a,106 b, and 106 c to predetermined attachment positions of the secondattachment surface 154. Thus, the time for the manufacturing operationcan be reduced as compared to the case where the rear surface of thesecond key attachment portion 124 b in which each of the key bodies 106a, 106 b, and 106 c is provided is positioned at each of the first tothird attachment regions 154 a, 154 b, and 154 c.

The flexible substrate 54 and the holder 56 according to this embodimentare formed so that the flexible substrate 54 is easily positionedrelative to the holder 56 and so that the flexible substrate 54 can beeasily affixed to the holder 56. Thus, according to the operationsection 12 and the endoscope 10 including the operation section 12 inthis embodiment, it is possible to reduce number of assemble processeswhile also improving assembly workability.

It is possible to regulate the movement of the first key attachmentportion 124 a of the flexible substrate 54 relative to the firstattachment surface 152 in the longitudinal direction L2 by engaging thefirst engagement protrusions 186 a and 186 b of the first attachmentsurface 152 with the first engagement recesses 126 a and 126 b of theflexible substrate 54. Thus, detachment of the first key attachmentportion 124 a from the first attachment surface 152 can be difficulteven if force is continuously applied to detach the first key attachmentportion 124 a of the flexible substrate 54 from the first attachmentsurface 152.

It is also possible to regulate the movement of the second keyattachment portion 124 b of the flexible substrate 54 relative to thesecond attachment surface 154 in the longitudinal direction L2 byengaging the second engagement protrusions 188 a and 188 b of the secondattachment surface 154 with the second engagement recesses 128 a and 128b of the flexible substrate 54. Thus, detachment of the second keyattachment portion 124 b from the second attachment surface 154 can bedifficult even if force is continuously applied to detach the second keyattachment portion 124 b of the flexible substrate 54 from the secondattachment surface 154.

Furthermore, even if the press body 74 a is pressed during the use ofthe endoscope 10, the first key attachment portion 124 a of the flexiblesubstrate 54 is fixed to the first attachment surface 152 by theadhesive agent, and the engagement protrusions 186 a and 186 b areengaged with the first engagement recesses 126 a and 126 b. Even if thepress bodies 76 a, 76 b, and 76 c are suitably pressed during the use ofthe endoscope 10, the second key attachment portion 124 b of theflexible substrate 54 is fixed to the second attachment surface 154 bythe adhesive agent, and the engagement protrusions 188 a and 188 b areengaged with the engagement recesses 128 a and 128 b. It is thereforepossible to effectively prevent the displacement of the flexiblesubstrate 54 relative to the holder 56.

The engagement protrusions 186 a and 186 b are separated relative to thelongitudinal direction L3 in the width direction in the first attachmentsurface 152 in particular. It is therefore possible to resist twistingwhen the first key attachment portion 124 a is twisted during or afterthe attachment of the first key attachment portion 124 a to the firstattachment surface 152.

In the second attachment surface 154, the engagement protrusions 188 aand 188 b are separated along the longitudinal direction L3. This canprevent the displacement of the second key attachment portion 124 b ofthe flexible substrate 54 along the longitudinal direction L2 thereofrelative to the longitudinal direction L3 of the second attachmentsurface 154.

The cavity portion 138 is formed not only by communicating the first andsecond openings 134 and 136 but also by communicating the third andfourth openings 172 and 174. In this instance, the space of the cavityportion 138 is formed by use of not only one of the third and fourthopenings 172 and 174 but also both of the third and fourth openings 172and 174. Especially, the third and fourth openings 172 and 174 do notreach the opposite side surface. Thus, the opening amounts of the thirdand fourth openings 172 and 174 can be smaller than when the third andfourth openings 172 and 174 pierce from one side surface 146 to theother side surface 148 with the same shape. It is therefore possible tomaintain suitable strength in the vicinity of the top 150 of the body132 of the holder 56.

In the example described here, the flexible substrate 54 is guided intothe cavity portion 138 from the outside of the body 132 through thesecond opening 136, and the flexible substrate 54 is guided to theoutside of the body 132 from the inside of the cavity portion 138through the first opening 134. Alternatively, the flexible substrate 54may be guided into the cavity portion 138 from the outside of the body132 through the first opening 134, and the flexible substrate 54 may beguided to the outside of the body 132 from the inside of the cavityportion 138 through the second opening 136.

Although it has been described here that the second belt-shaped portion122 b of the flexible substrate 54 is smaller in width than the firstand second key attachment portions 124 a and 124 b, the width may be thesame if the second belt-shaped portion 122 b can be bent. Although ithas been described that the first and second key attachment portions 124a and 124 b are displaced in the width direction that intersects atright angles with the longitudinal direction L2, the first and secondkey attachment portions 124 a and 124 b do not always need to bedisplaced.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and representative embodiments shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

What is claimed is:
 1. An endoscopic operation section to operate an endoscope, the endoscopic operation section comprising: an elastically deformable belt-shaped flexible substrate which is disposed inside the endoscopic operation section and which has a switch function; and a holder which is disposed inside the endoscopic operation section and which fixes the flexible substrate, the holder including: a top formed in the outer circumference of the holder, a first opening to pass the flexible substrate into the holder from the outside of the holder, a second opening to pass the flexible substrate to the outside of the holder from the inside of the holder, the second opening being provided so that the top is provided between the first opening and the second opening in the outer circumference of the holder, a cavity portion formed inside the holder to communicate the first opening and the second opening, a first attachment surface to which the flexible substrate is attached, the first attachment surface being adjacent to the first opening on the opposite side of the first opening from the top in the outer circumference of the holder, and a second attachment surface which is adjacent to the second opening on the opposite side of the second opening from the top; wherein: the cavity portion is defined by a ceiling portion and a bottom surface portion which is spaced from the ceiling portion and which faces the ceiling portion, and the belt-shaped flexible substrate is loosely provided between the ceiling portion and the bottom surface portion without contacting the ceiling portion and the bottom surface portion when the holder fixes the belt-shaped flexible substrate.
 2. The endoscopic operation section according to claim 1, further comprising an operation section main body which forms an outer shell of the endoscopic operation section, the elastically deformable belt-shaped flexible substrate and holder being housed within the operation section main body.
 3. The endoscopic operation section according to claim 2, wherein: the flexible substrate includes: a first key attachment portion in which a first key portion that is operated by pressing from the outside of the operation section main body is provided and which is attached to the first attachment surface, a second key attachment portion in which a second key portion that is operated by pressing from the outside of the operation section main body is provided and which is attached to the second attachment surface, and a flexible belt-shaped portion provided between the first and second key attachment portions, and the belt-shaped portion is configured to be deformed so that the first and second key attachment portions substantially face each other.
 4. The endoscopic operation section according to claim 3, wherein: the holder includes first and second side surfaces which are adjacent to the first and second attachment surfaces and which are separate from each other, and the top is provided between the first and second side surfaces.
 5. The endoscopic operation section according to claim 4, wherein: a third opening which communicates with the cavity portion is formed in the first side surface, and a fourth opening which communicates with the cavity portion and which is continuous with the ceiling portion is formed in the second side surface.
 6. The endoscopic operation section according to claim 5, wherein: the first key attachment portion, the belt-shaped portion, and the second key attachment portion of the flexible substrate are provided along a longitudinal direction of the flexible substrate, and a space between a distal end distally-positioned from the third opening toward the second side surface and a distal end distally-positioned from the fourth opening toward the first side surface has a width greater than a width of the belt-shaped portion that intersects at right angles with the longitudinal direction.
 7. The endoscopic operation section according to claim 3, wherein: the first key attachment portion, the belt-shaped portion, and the second key attachment portion of the flexible substrate are provided along a longitudinal direction of the flexible substrate, and the ceiling portion has a width greater than a width of the belt-shaped portion that intersects at right angles with the longitudinal direction.
 8. The endoscopic operation section according to claim 3, wherein the cavity portion houses the belt-shaped portion.
 9. The endoscopic operation section according to claim 3, wherein: the cavity portion includes: a guide portion which guides the flexible substrate into the cavity portion from the outside of the holder through one of the first and second openings and which guides the flexible substrate to the outside of the holder from the inside of the cavity portion through the other of the first and second openings, and a housing portion located adjacent to the guide portion that houses the belt-shaped portion in a state where the belt-shaped portion is bent between the bottom surface portion and the ceiling portion when the first key attachment portion is attached to the first attachment surface and the second key attachment portion is attached to the second attachment surface.
 10. The endoscopic operation section according to claim 3, wherein: the second key portion has key bodies provided in the second key attachment portion of the flexible substrate, the second attachment surface has at least one bent portion, the second key attachment portion of the flexible substrate has an abutment portion which abuts on the bent portion, and the flexible substrate includes, in a surface of the second key attachment portion opposite to a surface to which the second key portion is attached, a coated portion which is coated with an adhesive agent to the second attachment surface, an uncoated portion which is not coated in a part corresponding to the abutment portion, and a mold release sheet which integrally covers the coated portion and the uncoated portion and which is configured to be released from the coated portion.
 11. The endoscopic operation section according to claim 3, wherein: the first key attachment portion, the belt-shaped portion, and the second key attachment portion of the flexible substrate are provided along a longitudinal direction of the flexible substrate, and the first attachment surface has a first engagement portion which is configured to engage with the first key attachment portion of the flexible substrate and which regulates the movement of the flexible substrate in the longitudinal direction.
 12. The endoscopic operation section according to claim 3, wherein: the first key attachment portion, the belt-shaped portion, and the second key attachment portion of the flexible substrate are provided along a longitudinal direction of the flexible substrate, and the second attachment surface has a second engagement portion which is configured to engage with the second key attachment portion of the flexible substrate and which regulates the movement of the flexible substrate in the longitudinal direction.
 13. The endoscopic operation section according to claim 1, wherein: the first attachment surface has, at an end separate from the top, a first passage which guides the flexible substrate into the holder, and the second attachment surface has, at an end separate from the top, a second passage which guides the flexible substrate into the holder.
 14. An endoscope comprising: the operation section according to claim 1; an insertion section coupled to the operation section; an illumination optical system provided inside the operation section and the insertion section; and an observation optical system which is provided inside the operation section and the insertion section and which is provided in parallel with the illumination optical system. 